and make reading file streaming allowed to return 0 byte reads.
According to Microsoft documentation, on Windows it is possible to get
0-byte reads from pipes when 0-byte writes are made.
The defer causes two problems:
1. keeping the state active during call to NtCancelIoFile
2. invalid state transition. after canceled is returned from
checkCancel, new status is already canceled. calling finish after
that is illegal.
When `NtReadFile` returns `SUCCESS`, the APC routine still runs when
next alertable, which was previously clobbering an out of scope `done`.
Instead of adding an extra syscall to the success path, avoid all APC
side effects, allowing instant completions to return immediately.
As mlugg pointed out those race when a thread finishes an operation just
after it is canceled and then that thread to picks up another task,
resulting in these fields being potentially overwritten.
This updates fileReadStreaming on Windows to handle being alerted, and
then manage its own cancelation of the file I/O.
For now, let us refrain from putting the sync mode into the Io.File
struct, and document that to do concurrent batch operations, any Windows
file handles must be in asynchronous mode. The consequences for
violating this requirement is neither illegal behavior, nor an error,
but that concurrency is lost. In other words, deadlock might occur. This
prevents the addition of flags field.
partial revert of 2faf14200f58ee72ec3a13e894d765f59e6483a9
This tracks whether it is a file opened in synchronous mode, or
something that supports APC.
This will be needed in order to know whether concurrent batch operations
on the file should return error.ConcurrencyUnavailable, or use APC to
complete the batch.
This patch also switches to using NtCreateFile directly in
std.Io.Threaded for dirCreateFile, as well as NtReadFile for
fileReadStreaming, making it handle files opened in synchronous mode as
well as files opened in asynchronous mode.
This error is actually only ever directly returned from `std.posix.getcwd` (and only on POSIX systems, so never on Windows). Its inclusion in almost all of the error sets its currently found in is a leftover from when `std.fs.path.resolve` called `std.process.getCwdAlloc` (https://github.com/ziglang/zig/issues/13613).
Code used `ReturnType`, comment used `T` (which is what is used in similar functions).
Reviewed-on: https://codeberg.org/ziglang/zig/pulls/31007
Co-authored-by: Robert Ancell <robert.ancell@gmail.com>
Co-committed-by: Robert Ancell <robert.ancell@gmail.com>
The stated reason for this commit was cancelation didn't work. On
further review, we know why cancelation didn't work, and recent
enhancements on master branch make it easy to make it work.
Meanwhile, not using overlapped means that multiple threads cannot use
the same open socket handle. I also added line comments to explain the
choice in this revert commit.
This reverts commit fd3657bf8c.
closes#31011reopens#30865
Finite field elements can be in regular or Montgomery form, and
chaining different operations use to require manual and error-prone
conversions.
Now:
- `add`, `sub` and `mul` convert the second operand to match the
first operand's form
- `sq` and `pow` preserve the input's Montgomery form
- `toPrimitive` and `toBytes` return `UnexpectedRepresentation` if
the element is in Montgomery form, preventing incorrect serialization
This is fully backwards compatible and allows seamless chaining of
operations regardless of their representation.
The vast majority of libc functions return `c_int` for the return value,
when setting errno. This utility function is for those cases.
Other cases can hand-roll the logic, or additional helpers can be added.
IPPROTO_RAW (255) was missing from the Darwin/macOS IPPROTO struct,
even though it is defined in system headers and supported by the platform.
This is a commonly used protocol for raw IP sockets.
If the library isn't actually installed, `generated_bin` will be null,
causing this to panic about a missing dependency for itself; checking
for this state avoids this.
